Answer:
= 8/6435
Step-by-step explanation:
Number of black balls = 8
Number of Brown balls = 5
Total number of balls = 8+5 = 13
Pr (8 balls picked at random are black ) =
Number of black balls / Total number of balls.
1st Pr ( 8 balls picked are black) = 8/13
Pr (2nd random pick) = 7/12
Pr (3rd random pick) = 6/ 11
Pr (4th random pick) = 5/10
Pr (5th random pick) = 4/9
Pr (6th random pick) = 3/7
Pr (7th random pick) = 2/6
Pr (8th random pick) = 1/5
Pr (8 balls picked at random are black ) = 8/13 * 7/12 * 6/11 * 5/10 * 4/9 * 3/7 * 2/6 * 1/5
= 8/13 * 7/12 * 6/11 * 1/2 * 4/9 * 3/7 * 1/3 * 1/5
= 8/6435
But pls note, I solved it such that there wasn't a replacement after each pick.
Math is fun
